U.K. company develops new Fischer-Tropsch catalyst

By Ryan C. Christiansen
Web exclusive posted August 15, 2008 at 11:14 a.m. CST

Oxford Catalysts Ltd. in the United Kingdom has developed a new metal carbide Fischer-Tropsch catalyst that can be used in microchannel reactors to make second-generation biofuel production environmentally and economically viable.

The catalysts can convert synthesis gas to liquid sulfur-free diesel fuel, jet fuel, or naphtha, according to Derek Atkinson, business development director for the company.

After synthesis gas, a mixture of carbon monoxide and hydrogen, is produced through steam-reformation of methane produced from the anaerobic digestion of organic waste, or from the gasification of biomass through pyrolysis, Oxford's Fischer-Tropsch catalyst can be used in a microchannel reactor to convert the gas to liquid fuel at 70 percent efficiency, Atkinson said.

Microchannel reactors have channels with diameters in the millimeter range. The small diameter channels dissipate heat more quickly than conventional reactors with larger channel diameters in the 20 millimeter to 30 millimeter range and so more active catalysts can be used. Oxford produces the cobalt-based catalyst using its patented organic matrix combustion method, which fixes catalyst crystal sizes within the 8 nanometer to 15 nanometer diameter range. The crystals also exhibit terraced surfaces. Both features enhance the catalyst activity to a level that is optimal for microchannel reactors, the company said.

Although they are more efficient, microchannel reactors are designed to produce fuel on a small scale: up to 50 barrels per day. One application is to bring the reactors to the source of the feedstock for fuel production, because the reactors require one metric ton of agricultural waste biomass to produce one barrel of liquid fuel. However, "since the reactors are modular, you can easily put several reactors together," Atkinson said. "There is nothing to stop them from being used for plants ranging in size from 50 to 1 million barrels per day." He said plants could start small and build up to their capacity. The first plants to be commercialized will produce thousands of fewer fuel barrels per day, Atkinson said.

Oxford expects to have at least two demonstration plants come on-line next year. "We are commercializing the catalyst with a catalyst manufacturer and expect to be able to supply multi-[metric ton] quantities by the end of this year," Atkinson said.

While Oxford's catalyst was designed to optimize reaction in microchannel reactors, Atkinson said the company can use the same catalyst production technique to produce catalysts for other types of reactors. He said the technology can also be used to improve existing catalysts.

Atkinson said the company's catalyst production technology is based on more than 20 years of research at Oxford University. The company itself spun off from the university in 2004, he added.